TECHNICAL FIELD
The present invention relates generally to bi-level halftone processing circuits and image processing apparatus such as facsimiles (hereinafter referred to as "FAX") and copying machines using the same. More particularly, the present invention relates to bi-level halftone processing circuits for use in image data processing circuits including FAX and copying machines in such a way as to output variable halftone image display data spuriously as binary data by substituting spatially distributed binary values "0", "1" for the variable density of input images, and to FAX, copying machines and the like using the circuit stated above.